This Silencer Hazard Map Brief documents the free field blast overpressure hazards from the Apparition Instruments AI 3CM silencer in the long and short configuration fielded on the 6.75-in Sig MCX 300 BLK AR-18 Rifle semiautomatic rifle firing Discreet Ballistics 190gr subsonic 300 BLK ammunition, as evaluated in technical Report 6.235 and as tabulated in record numbers 7.1.275 and 7.1.276 in the Rankings, respectively.